Renewable fuse



Feb. 16 1926.

G, R. TRUMBULL RENEWABLE FUSE Filed August 29, 1921 INVENTOR George R. Trumbull,

l Vhen a fuse blows, a

Patented Feb. 16, 1926.

PATENT QFFICE.

GEORGE R. TRUMBULL, OF BANTAM, CONNECTICUT.

RENEWABLE FUSE.

Application filed August 29, 1921.

To all 107mm l? may concern:

Be it known that GEORGE R. TRUMBULL, a citizen of the United States of America, residing at Bantam, Litchfield County, Connecticut, have invented a new and useful Renewable Fuse, of which the following is a specification.

lf'ly invention relates to a renewable fuse and is in some respects similar to the invention disclosed in my cro-pending application, Serial No. 495,030, liled August 2st, 1921.

Ordinary renewable fuses may be readily overloaded by simply substituting for the fuse link intended to be used` a strip of metal of greater current carrying capacity. great amount of heat is generated and the fuse link is often par tially vaporized, and this vapor added to the heated air in the fuse causes great pressure within the fuse which cannot be absorbed quickly by the body of the fuse which is usually of insulating material.

lt is an object of my invention to provide novel means for rendering the overloading of renewable fuses very difficult or practically impossible.

lt is a furtherrobject to provide novel means forrpreventing to some extent the generation of hieh pressures within the fuse body.

It is a further object to provide a novel indicator for renewable fuses.

ther objects and features of invention will be apparent as the specification proceeds.

Briefly stated in the preferred form of my invention, there is provided a fuse body usually of insulating material and a fuse linkextends through the body and is suitably secured at the ends. lithin the body are positioned one or more metallic guard washers. Between the guard washers (when two are provided) is usually positioned a metallic indicator. The guard washer and indicator are so formed as to permit the passage of the fuse link through the body. The fuse link in the preferred form is of irregular transverse cross-section for at least a portion of its length, and the passages in one or more of the parts through which the link passes is preferably made to Helfern@ .in eliapesubstaetally t0 the form of fuse link suitable for my Serial No. 496,322.

section of the irregular portion of the fuse link.

ln the drawings, l have shown for illustrative purposes only a preferred embodiment of the invention.

Fig. l is a longitudinal sectional view of a fuse embodying features of my invention.

Fig. 2 is a detail perspective view of one invention.

Fig. 3 is a detail perspective view of two guard washers and an indicating member separated from the fuse body and from each other.

Fig. lis an end view of a batlle at one end of the fuse.

Fig. is a similar view of the same baille shown in Fig. l but viewed from the re verse side.

F ig. G is an end view of an end Cap at one end of the fuse. A

Fig. 7 is a similar view of an end cap at the other end of the fuse.

Fig. 8 is a fragmentary section of a detail.

In said drawings, the body of the fuse which is usually of insulating material is indicated at l0. In the form shown, the body has screw threaded thereon the end caps 11.-12, preferably of hardened steel, each cap having passages 13 14 for the fuse link l5. Cover caps 16-17 have been shown in screw threaded engagement with the end caps ll--l2- The ends of the fuse ink are preferably held between the cover caps, and in the form shown I have disclosed baffles 18-19 between the caps at each end of the body. These batlles it will be noted are slightly spaced from the cover caps as indicated at 20 to permit the passage of gases generated when the fuse is blown.

The fuse link as herein disclosed provided with a part intermediate its ends of reduced cross-section in order to cause the fuse to rupture at this point. At least a part of the fuse is of irregular transverse crosssection and the specific fuse link shown corrugated best villustrated at 21 Iin Fig. 2. The oppositeend of the fuse link may be a plain 'flat strip, and the extreme end .may extendto the outside of the body and bear a legend (not shown) to indicate `ment with the tube l() may likewise tend to hold the end cap against unserevving.

lillhile I have described in detail a speeitic form of the invention, I Wish it understood that various changes may be made Without departing from the spirity and scope of the invention as defined in the appended claims I claim:

1. In a fuse, a fuse body having end caps thereon with passages for a tuse link, a metallic guard Washer nitliin said body and removed a substantial distance from the ends thereoin4 and having a passage for a link, said guard Washer having angularly bent spring arms for holding the same Within the body, fuse link extending through the passages and means for making contact with the iuse link at the ends of the body.

2. In a fuse, a fuse body, a pair ot guard Washers in said body each having an angularly bent spring portion for holding the latter in place, said Washers being positioned in proximity to each other and removed from the ends of the fuse body and having fui passages therethrough for a fuse link, and means for making electrical contact With said fuse link at the ends ot' the body.

8. In a fuse, a fuse body and a fuse link therein, a guard Washer having aholding arm extending at an angle thereto for securing the same in the body, an indicating member observable from the outside of the fuse body, said indicating member being positioned adjacent tol so as to be guided by said guard Washer, said guard Washer and indicating member having passages therethrough for the fuse link.

4. In a fuse, a fuse body and a 'fuse link therein, an indicating member Within the body and observable Jfrom the outside thereor, a separate guard Washer Within the body at each side of said indicating member, said guard Washers being positioned adjacent to so as to act as guides for said indicating member, said indicating member and guard Washers having passages for the fuse link.

5. In a fuse, a fuse body and a fuse link therein, a pair of guard Washers Within said body, one ot said Washers having'4 a toot thereon for spacing the Washers apart, said washers having passages 'tor the fuse link.

(3. In a ituse, a :tuse body and a fuse link therein, a metallic guard Washer nithin said body and having an arm for holding the washer in place, said `fuse link having a part thereof of irregular cross-seetion and said washer having a passage for the 'fuse link and conforming substantially in shape thereto, said iliuse link extending through and beyond said passage and being secured to said use body independently ot said guard Washer.

7. In a fuse, a fuse body and a fuse link therein, a pair oit guard Washers in the body and having spring arms for positioning the latter, one of said washers having i'eet thereon itor spacing the washers apart, said Washers having passages therein tor the fuse link.

8. In a fuse, a fuse body, end caps on said body and having fuse link passages therein, one ot said end caps being of hardened steel and the passage therein being of predetermined irregular shape, a fuse link in said fuse body and extending through said passages and secured outside ot said end caps, a part of said fuse link being oit substantially the same irregular form as one of said passages.

9. In a fuse, a fuse body and a fuse link therein, a pair ot metallic guard Washers in said body, a metallic indica-tor Within said body and in proximity to and between said guard Washers, said metal indicator having a head of insulating material observable from the outside of the body.

l0. In a fuse, a fuse body and a fuse link therein, a pair of metallic guard Washers held in said body, a metallic indicator With in said body and between said Washers and guided thereby, said washers and indicator having passages for the fuse link.

l1. In a fuse, a fuse body and a 'fuse link therein, a metallic guard Washer in said body and having spring arms extending therefrom at an angle thereto whereby the wanner may be forced into the body from one end and will be prevented by said spring arms from being Withdrawn from the same end.

12, In a fuse, a fuse body having end caps thereon and having passages for a ruse link, a pair of cover caps for said body, a Ytuse link Within the body and With the ends held between said caps at each end or" the body, a pair of metallic guard Washers in said body and spaced apa-rt from each other, a metallic spring pressed indicator Within said body and adjacent; to and between said Washers, said indicator having a head of insulating material observable from the outside o said body, said Washers and indicator having passages for the fuse link.

13. In a fuse, a fuse body and a fuse link therein, a metallic Washer Within said body and having a passage for the fuse link and an insulating Washer Within said body and interposed between said metallic iashcr and one end ot the `fuse body .o prevent arcing between the washer and said end ot the fuse.

141-. As an article of manufacture, a guard *asher for a fuse comprising a metallic plate having a spring arm thereon and extending at an angle thereto` said washer having a passage therethrough.

l5. As an article of manufacture, a guard vfasher for a fuse comprising a metallic plate of spring steel having a pair ot spring arms extending therefrom at an angle thereto, said Washer having a passage therethrough.

16. As an article of manufacture, a guard Washer for a fuse comprising av metallic plae having ar spring arm thereon, al foot thereon and having a passage therein.

17. In a fuse, a fuse body, a hardened steelwasher in said fuse body and having a. passage therein of predetermined irregular shape, a fuse link in sadbody and extending 

